Safety-valve.



Patented Oct. 5, 1909. I

Att'y.

W. V. TURNER. .SAFETY VALVE.

-'APPLIUATION'IHBD181M219,1906.

NESSES UNITED STATES PATENT OEFTCE.

WALTER V. TURNER, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE WEST-INGHOUSE AIR BRAKE COMPANY,'-OF OF PENNSYLVANIA.

PITTSBURG, PENNSYLVANIA, A CORPORATION SAFETY-VAIJVE.

Specification of Letters Patent.

Patented Oct. 5, 1909.

Application filed September 19, 1905. Serial No. 279,156.

certain new and useful Improvement in Safety-Valves, of which thefollowing is a specification.

This invention relates to safety valves and more particularly to thatclass known as pop safety valves, in which the opening and closing ofthe valve occurs in a prompt and positive manner. The main object of myinvention is to provide an improved safety valve of this type'fin whichthe'valve will instantly moye to a Wide 0 en position as soon as itbegins to open un. er the pressure of the air, steam or other fluid, andwhen the pressure is dimmished a certain amount, will then move quicklyand positively to its seat by means of an opposing fluid pressure actingin conjunction with the spring.

Another feature of my invention relates to means for readily adjustingthe range or amount of fall in pressure between the opening and closingpoints of the valve.

In the aocompanyhig drawing, Figure 1 is a vertical section of a safetyvalve device embodying my improvements, and taken on the line az-m ofFig. 2, and Fig.2 is a horizontal section taken on the line y y of- Fig.1.

ccording to the construction shown the safety valve devlce comprises abody portion 3, containing-a valve chamber 18, springchamber 19, and apassage 4 leading from the valve seat and adapted to communicate with aboiler, reservoir, cylinder or other rcce tacle containing steam, air,or other fluid under pressure. 4 1

A small huddling chamber 6 ma be formed just above the valve seat anvalve 5 ma be provided with an annular lip ortion 7 or receiving theimpact from the our of fluid as the valve begins to 0 en. to assist 1ncausing the valve to imm 'ately rise to a wide open position. Above thevalve ismounted a s ring 13, with ste n 12,

adjustable nut 15 an cap nut 16.

rdlng to. my invention, a movable phutimntorpiskon, subject to fluidpressure, is employed for ass stmg the, closing move the merit of-thevalve, and for'this purpose I prefer the construction shown in thedrawingyin which the piston 9 is connected d1- re'ctly to the valve 5and operates in a bushto this arrangement the spring chamber 1 9 alsobecomes a pressure chamber and is adapted to receive fluid underpressure from the valve chamber through one or moreports 11 formed inthe bushing 8. These ports 11 are controlled by the movement of thepiston, as are also the outlet ports 10, of which there may be anydesired number, the location being such that when the valve is closed,

- ing 8 abovethe valve chamber. According as indicated in the'drawing,the outlet ports 10 are also closed while the 'pressure ports 11 areopen, .and when the piston rises to open the outlet ports 10, it alsocloses the ports 11..

One or more small vent ports 14: are pro vided for the pressure chamber19, and the capacity of these vent ports bears a certain relation to thecapacity of the pressure supply ports 11 to give the desired action ofthe valve in closing.- This relation may be varied to suit differentconditions by means of the adjustable nut or ring 17 which may be turnedto regulate the capacity of the vent ports 14 and thereby regulate theamount of fall in ressure between the opening and closing of the valve.

The 0 oration is as follows :-The spring being a justed to the pressureat which it is desired that the valve shall open, when this pressureaccumulates on the face of the valve and raises it slightly from itsseat, the fluid flows out in an annular jet and by the additional forceofthe impact or pressure then exerted upon the amiular flange 7immediately raises the valve and piston to open more or less widely theoutlet orts 10 and close the pressure ports 11. T 's prevents, for thetime being, the accumulation of pressure in chamber 19, while thepressure in the valve chamber exertedon under side of iston 9 alsoassists in this movement. I the pressure is then relieved by blowing 01!through the outlet ports 10 and diminishes to a po nt at which thespring 13 starts the valve and piston downward, the

ports 11 begin to open and permitthe passage oi t9 the chamber 19.. Thepressurethen accumulates inchamber 19 on the upper face of the pistonmore or less rapidly, a variable fluid pressure for effecting a quickcorresponding to the relative capacities of the ports 11 and 14:, andacting in conjunction with the spring immediately carries the valve toits seat with a prompt and positive movement, thereby cutting off thedischarge through the valve chamber and ports 10 and also the supplythrough ports 11 to the pressure chamber. The pressure in chamber 19then immediately equalizes with the atmosphere through vent ports 14.

By adjusting the vent ports to a large area or capacity it will be seenthat the rise in pressure in chamber 19 from the supply through ports 11will be very slow, so that the closing movement of the 'valve' will bedelayed and a correspondingly larger drop in pressure in the receptaclewill occur; while if the-capacity of the vent port or ports is made verysmall the accumulation of pressure in chamber 19 will be so rapid assoon as the ports 11 begin to open as to instantly force the valve toits seat, thereby permitting only a slight fall in pressure. In thismanner, the valve device may be readily adjusted to suit differentconditions of service.

The extent to which the valve rises at any given time to open the outletports 10 depends, of course, upon the capacity of the valve, the volumeof the receptacle and the rate at which the pressure is increasingtherein, but when the valve moves to its extreme wide open position thestem 12 strikes the stop 20 on the cap nut and prevents furthermovement.

My improved safety valve device has the advantage of securing a promptand positive closing of the valve upon any given degree of drop inpressure and maintains this degree constant throughout long periods ofuse. It is also adjustable to suit all kinds and conditions of service.

While my improvement is designed for general application as a safetyvalve and the invention is not limited to any particular use of thedevice, it may be mentioned that it is especially adapted for use inconnection with compressed air reservoirs and brake cylinders of an airbrake system.

Having noW described my invention, what I claim as new and desire tosecure by Let ters Patent is 1. A safety valve device, comprising avalve, a spring tending to close said valve, a piston connected to thevalve, means for supply ng fluid under pressure to one side of saidpiston to effect a quick closing of the valve, and means for releasingsaid fluid when the valve is closed.

2. A safety valve device comprising a valve adapted to be opened byfluid pressure, an adjustable spring tending to close said valve, and apiston subject on one side to closing of the valve.

A safety valve device comprising a valve adapted to be opened by fluidpressure, a spring tending to closethe valve, an outlet port, or ports,for the discharge of fluid under pressure, a piston subject on one sideto the pressure in a chamber for tending to close said valve, and meanscontrolled by the movement of the piston for varying the pres sure insaid chamber to effect a quick clos ing of the valve.

l. A safety valve device comprising a valve adapted to be opened byfluid pressure. a

spring tending to hold said valve closed. an

outlet port, or ports, for discharging fluid under pressure, a pressurechamber, a piston connected to the valve and subject to the pressure insaid chamber, and a port controlled by the movement of the piston forsupplying fluid under pressure to said chamber to effect a quick closingof the valve.

5. A safety valve device, comprising, a valve, a spring tending to holdthe valve closed, a piston connected to said valve and subject on oneside to a variable fluid pressure, means for cutting off the supply offluid pressure to the piston when the valve is closed, and an outletport of ports controlled by said piston.

6.'A safety valve device, comprising a valve, a spring tending to holdthe valve closed, a pressure chamber, a piston connected to the valveand sub ect to the pressure in said chamber, an outlet port controlledby the piston, and a port also controlled by the piston for supplyingfluid under pressure to said chamber.

7. A safety valve device, comprising a valve, a spring tending to holdthe valve closed, an outlet port, or ports, for the discharge of fluidunder pressure, a pressure chamber having a. small vent port, a pistonconnected with said valve and subjectto the pressure in said chamber,and. a port controlled by the movement of the piston' for supplyingfluidto said chamber, to effect a quick closing of the valve.

8. A safety valve device, comprising a valve, a spring tending to closethe valve, a pressure chamber havmg a vent port, means for adjusting thearea or capacity of the vent port, a pistonconnected with said valve andsubject to the pressure in said chamber, and means controlled by themovement of the piston for supplying fluid under pressure to saidchamber.

9. A safety valve device, comprising a valve, a spring tending to closethe valve, a valve chamber, a pressure chamber, a piston connected withsaid valve and subject to the pressure in the pressure chamber, anoutlet port or ports from'the valve chamber controlled by tire movementof the piston, and

.a port from the valve chamber to the pressure chamber also controlledby the movement of the piston.

' -10. A safety 'valve device, comprising a valve, a spring tending tohold said valve valve a-spring tending to hold said valve the valve tormomentarily opening and then close a piston connected to the valve, andmeans operated by the closing movement of of the valve, and outlet portscone closing the supply offluid to one side of said piston, to effectthe valve.

closing movement of ;the

12. A safety valve device, comprising a valve, a spring tending to holdsaid valve closed, a piston connected to thevalve and subject to fluidpressure-tending to hold said valve open, and means operating upon thepreliminary closing movement of the Valve for hastening said movement.

In testimony whereof I have hereunto set my hand. a 4

WVALTER V. TURNER.

l/Vitnesses:

R. F; EMERY,

J. B. MACDONnm.

